Veil to Unveil: Aquinas on the Mystery of the Mass
Thomistic theology is rarely associated with liturgical prayer, even by many of St. Thomas’ own disciples. Such a dissociation reveals more about the priorities of later Thomism, however, than it does about St. Thomas Aquinas, who himself devoted considerable energy to the contemplation of the sacred liturgy. In fact, the longest question of the Summa theologiae is about the meaning of the Old Law’s liturgical rituals (1-2.102). The question of the Summa with the most articles is the question on prayer (2-2.83). And no article in the Summa theologiae has more objections than the one about what can go wrong in the celebration of Holy Mass (3.83.5). If we are to renew our liturgical formation through the “rediscovery of a theological understanding of the liturgy,” therefore, as the Holy Father has called for in Desiderio Desideravi, then it is important for us to include the contribution of the theologian par excellence, the Common Doctor of Holy Church, St. Thomas Aquinas.
One place we should look is to St. Thomas’ mystagogy of the Mass—that is, his theological teaching on the meaning and purpose of its various rites, for the sake of helping his fellow Christians better understand the mysteries they celebrate. Unlike his teacher St. Albert the Great and many of their contemporaries, St. Thomas never wrote a stand-alone commentary on the Eucharistic liturgy. Nevertheless, and unbeknownst to many, St. Thomas did write his own expositio Missae or “explanation of the Mass.” In fact, he wrote two: one in his earliest major work, the Sentences commentary (4.8.ex); the other in his latest, the Summa theologiae (3.83.4). Both of these treatments include a division of the liturgy into its essential parts, as well as a thorough study of the words that comprise each part—that is, “the things said around this sacrament,” the many words of the whole Mass that surround the few words of institution. For although only that barest form is necessary for the mere being of the sacrament, all the words of the rite are necessary for its well-being. “Because in this sacrament the whole mystery of our salvation is embraced,” he says, “thus it is carried out with greater solemnity.” Moreover, like every sacrament, the Mass signifies “in a twofold way, namely by words and by deeds.” Thus both in the Sentences (4.12.ex) and in the Summa (3.83.5), Thomas supplements his commentary on the words of the Mass with a further reflection on its actions and gestures—which, he assures us, “are not ridiculous gesticulations, for they are done to represent something.”
